Thallus
Foliose, up to 3 cm in diameter, formed of small narrow lobes, thallus often not clearly visible because entirely covered with apothecia
Color
Upper surface yellow-orange (in the sun) to greyish (in the shade)
Reproduction
Apothecia: numerous, in tight groups that can cover and hide the entire thallus
Soralia: absence
Isidia: absence
Substrate
Mainly on branch, sometimes on trunk or non-calcareous rock
Habitat
Heliophilous and nitrophilous
Sensitivity to air pollution
Moderately sensitive to pollution